In comparison, Hillary Clinton has an 83 percent favorable rating among Democrats but only 15 percent with Republicans, reports The Wall Street Journal.

"It's very unusual data," said Bill McInturff, a partner at Public Opinion Strategies, a co-director of the poll. "We don't have a lot of numbers where we have a partisan figure whose positive ratings are higher with the opposite party.''

Christie's campaign office declined to comment about the poll, but his appeal for Democrats was on display again Tuesday when he chose a special election to replace the late Democratic Sen. Frank Lautenberg, rather than appoint a Republican to the post until 2014 as he could have done under New Jersey law. The Democrats are widely expected to hold on to the seat.

On Tuesday, Christie won the GOP gubernatorial primary against token opposition and will face the Democratic primary winner, state Sen. Barbara Buono, in November.

Jennifer Duffy, senior editor at Cook Political Report, told the Journal the increased support by Democrats could make it difficult for Christie to win a presidential primary. "He can get elected president if he can win the nomination," she said. "It's winning the nomination that's a problem."

State Assemblyman John Wisniewski, who chairs the New Jersey state Democratic Party, dismissed the findings.

"It's a snapshot in time," he told the Journal. "I don't think it says much of anything."

Christie's popularity among Democrats has been given a boost through a series of appearances with President Barack Obama in the wake of Superstorm Sandy. But his stand on most issues is to the right of most members of the party, including tough stances on teachers' unions, public employees, and laws on abortion and same-sex marriage.